By Andi Small | Updated Aug 30, 2022
An electromagnet is created when an electric current flows through a coil of wire wound around a ferromagnetic core, such as iron. The current aligns the core’s magnetic domains, amplifying its magnetic field. This hands‑on project demonstrates how electricity and magnetism work together and is perfect for a quick science demonstration using a 9‑V battery.
Measure and cut a length of insulated copper wire roughly four times the length of your steel nail. Strip about half an inch of insulation from each end with a wire stripper so the metal conductor is exposed.
Tightly wrap the wire around the nail, keeping the turns snug so each loop touches the next. Continue winding until the wire reaches the nail’s length. Leave a few inches of wire on each end so you can connect them to the battery clip.
Twist each exposed end of the coil with the corresponding stripped end of the 9‑V battery connector. Place the spliced wires inside a splice cap, then secure the cap by tightening it with pliers or crimping it. Repeat for the second end.
Attach the battery to the connector clip. Once all connections are secure, the coil will become a magnet. Test it by bringing it near a ferrous object or another magnet to see it attract or repel.
Enjoy this simple experiment and explore how changing the number of turns or the battery voltage affects the magnetic strength.
